1. Field of the Invention
The present invention relates to a compact-size zoom lens system, especially of a type suited for a built-in zoom lens system of a lens shutter camera.
2. Description of the Related Art
A lens system built in a lens shutter camera is required to be compact, light-weight and low cost. When a zoom lens system is used in a lens shutter camera, the requirements are just the same. For making a zoom lens system compact including the lens shifting space for zooming the refractive power of every lens group must be strong. In order to obtain a strong refractive power of a lens group while maintaining a high optical quality, the number of lenses in the lens group should increase. However, the increase in the number of lenses naturally increases the weight and the cost. Thus, the prior art is still seeking to provide an improved compact-size zoom lens system.